Lamp unit



Nov. 8, 1938. H. BAUMHAUER ET AL 2,135,595

LAMP UNIT Filed March 5, 1935 INVENTORS 25M @azmzaau ORNEY Patented Nov. s, 1938 LAMP UNIT Heinrich Banmhauer,

Berlin- Spandau, and

Werner Fehse, Berlin-Lichterfelde, Germany, assignors to General Electric Company,.a corporation of New York Application March 5, 1935, Serial No. 9,514 In Germany March 9, 1934 2 Claims.

The present invention relates to lamp units generally and more particularly the invention relates to lamp units comprising a gaseous electric discharge lamp device and a heat conservator for said lamp device.

The object of the present invention is to provide a lamp unit comprising a gaseous electric discharge lamp device and a heat conservator which is easily and quickly assembled and taken apart. Another object of the invention is to provide a heat conservator for a lamp device the manufacturing cost of which is reduced to a minimum. Still further objects and advantages attaching to the device and to its use and operation will be apparent to those skilled in the art from the following particular description.

- In accordance with these objects the new and novel heat conservator comprises at least three concentric tubes of different diameter. The intermediate tube or tubes is joined to the tubes on either side thereof by fusing one end of said intermediate tube to an end of the tube on one side thereof and by fusing the opposite end of said intermediate tube to an end of the tube on the other side thereof. Each end of the conservator is open for the access'of air. -The heatconservator is clamped between two supporting elements which make a gas pervious mechanical joint with the respective ends of the heat conservator and said supports are removabiy attached to the lamp device surrounded by said heat conservator. The heat conservator is thus filled with air, which is a poor heat conductor, at the pressure'of the ambient. The lamp unit is easily assembled by inserting the lamp device in th'eheat conservator and attaching the clamping supports for the heat conservator onto the ends of the lamp. The lamp unit is taken apart just 'as easily. The heat conservator reduces the heat losses from the lamp device during the 0peration thereof and said lamp device operates at a higher temperature than .it would without said heat conservator. This is of advantage in connection with vapor lamps, such as cadmium vapor, magnesium vapor, sodium vapor, or mercury vapor lamps as the vapor pressure in the lamp is higher than it would be otherwise and greater efllciency is obtainable. Since the conservator is not evacuated the manufacturingcost thereof is very low.

In the drawing accompanying and forming part of this specification an embodiment of the inventionis shown in a schematic, partly sectional view. e

Referring to the drawing the new and novel lamp unit comprises a gaseous electric discharge lamp and a heat conservator "5, 6 l therefor. Said lamp consists of an elongatedtiibular container I having sealed into each endthereof a thermionic electrode 2 and having a gaseous at- 5 and each of said bases 3 has a pair of contact 10- pins 4 thereon which are connected by current leads to said electrodes 2.

Said heat conservator consists of three con-- centric tubes 5, 6 and 1. One end of said tube 6 is fused to an end of said tube 5 and the other 15 end of said tube 6 is fused to an end of said tube 1. The heat conservator is open at each end for the access of air. A threaded sleeve 8 having a ring flange 9 is screwed onto each of the Edison bases 3. The heat conservator is firmly clamped 20 between said flanges 9 and an annular pad ill of heat insulating material, such as,an asbestos pad, is interposed between each of said flanges 9 and the end of said heat conservator 5, 6 and 1.

The above described lamp unit is inexpensive 25 to manufacture, is easily and quickly assembled by screwing the sleeves 8 on the bases 3 to clamp "the heat conservator between the flanges 9 of the sleeves 8 and is easily taken apart by unscrewing said sleeves 8 from said bases 3. While 30 the ends of the heat conservator are open for the access of air, which is a poor conductor of heat, the flanges 9 and the pads i0 ,restrict the entrance of air into said heat conservator tothe extent that the flow of air, if any, through the 35 in the forms and details of the device illustrated 45 and in its use and operation may be made by those skilled in the art without departing from the broad spirit and scope of the invention.

What we claim as new and desire to secure by Letters Patent of the United States, is:- 50

1. A lamp unit comprising in combination an elongated gaseous electric discharge lamp device, a heat conservator therefor, said lamp device having a base attached to each end thereof, sup- P rts on said \bases for said conservator, said 55 three coaxial and coextensive glass tubes, one end of the intermediate tube being iused to an end of the tube having a greater diameter than said intermediate tube and the other end of said intermediate tube being fused to an end of the tube having a smaller diameter than said intermediate tube, the ends of said conservator being open and gas pervious means at the open ends of said conservator to restrict the-flow 01' air in said conservator.

- HEINRICH BAUMHAUER.

WERNER FEHSE. 

